This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. In 2010, we continued work on Aim 1: Characterize spontaneous activity in the BLA and PFC, and evaluate the presence of synchronous oscillations. We have collected data from six rats undergoing fear conditioning and extinction training, and have begun work on a manuscript describing our findings. We have demonstrated that delta (1.5-4Hz) and gamma (30-80Hz) frequency bands in the local field potentials of the BLA and mPFC show unique patterns of increased coherence during fear learning and expression, and that these patterns are not seen in rats that do not learn the fear association, indicating a functional relationship with the emotional state of the animal. We have now begun experiments related to Aim 2: Evaluate neural and behavioral response to PFC stimulation. We have applied electrical stimulation modeled after human DBS parameters to the mPFC region thought to be homologous to Cg25, while recording behavior and neural responses in the BLA. By stimulating during the fear extinction training protocol, we hope to demonstrate a suppression of negative emotion and an acceleration of extinction learning. The rats being used in this experiment have just arrived and are being weighed daily in preparation for food restriction, the first step in the protocol.